Are You Using Samsung Galaxy C7, You can now Check for a System Update and See if an OTA update is Available for your Device. A user from China has share a Screenshot of His Changelog When installing the New Update on his Samsung Galaxy.

Before the Update, Samsung Galaxy C7 is running on Android 6.0 Marshmallow withe other Specification like 4GB RAM and 32/64GB inbuilt Memory

The Update which now feature Always-On Display, Multi-window, and the
Settings menu will tend to increase Samsung Galaxy C7 Users Experience and it is about (1GB+) in File Size. The Update (Android 7.0 Nougat) Will make Samsung Galaxy C7 more efficient and Prompt Installation more faster as Samsung has include a Security Patch to the New Update.

Note: it is Advisable before making such update to Back Up your Files in case Something went Wrong..